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Home > Vol 9, No 3 (1999)

Sheila Sundaram

Wesleyan University Department of Mathematics Middletown CT 06459

We present a class of subposets of the partition lattice ( n - 1)!\frac n - k k (n - 1)!\frac{{n - k}}{k} . The posets Q _n ^k are neither shellable nor Cohen-Macaulay. We show that the S _n -module structure of the homology generalises the Whitehouse module in a simple way.

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